Batteries are useful for converting chemical energy into electrical energy, and may be described as primary or secondary. Primary batteries are generally non-rechargeable, whereas secondary batteries are readily rechargeable and may be restored to a full charge after use. As such, secondary batteries may be useful for applications such as powering electronic devices, tools, machinery, and vehicles. For example, secondary batteries for vehicle applications may be recharged external to the vehicle via a plug-in electrical outlet, or onboard the vehicle via a regenerative event.
One type of secondary battery, a lithium ion secondary battery, may include a negative electrode or anode, a positive electrode or cathode, and an electrolyte disposed between the positive and negative electrodes. The negative electrode may be formed from a material that is capable of incorporating and releasing lithium ions during charging and discharging of the lithium ion secondary battery. More specifically, during charging of the battery, lithium ions may move from the positive electrode to the negative electrode and embed in the material. Conversely, during battery discharge, lithium ions may be released from the material and move from the negative electrode to the positive electrode. As lithium ions incorporate into and release from the material of the negative electrode, the volume of the material may change.